Radiation from mobile phones causes changes in the brain
which could pose risks to health, an authoritative two-year study has concluded.

In ground-breaking research on the effects of radiation
on the brain - which has for the first time used human cells rather than
rats - scientists found that even low-level emissions from handsets affects
cells.

They believe the changes could disable a safety barrier
in the body which is meant to protect the brain from harmful substances
in the blood. The scientists are now calling for further research to discover
how important the effects on health might be.

The study, conducted by the Radiation and Nuclear Safety
Authority in Finland, found that exposing human cells to one hour of mobile
phone radiation triggered a response which normally only occurs when cells
are being damaged.

This led the cells which make up blood vessel walls to
shrink, allowing tiny molecules to pass through into brain tissue.

The report's conclusion warns: "The possible RF-EMF
(radiation-induced breakage of the blood-brain barrier), if occurring repeatedly
over a long period of time, might become a health hazard because of the
possible extra-capillary accumulation of molecules that might cause brain
tissue damage."

The study is a an important step forward in mobile phone
research because it has proved biochemical changes, which were found to
occur in rats, also occur in human cells. Scientists now need to discover
how the human body reacts to such changes and whether it can cope, or if
there are serious health threats.

Professor Darius Leszczynski, who will present the research
at a conference in Canada this month, said he could confirm that radiation
from mobile phones does affect the delicate make-up of human cells. "We
have shown there are biochemical changes in human cells," he told
the Evening Standard. "Other studies in animals have shown this can
lead to a leakage in the blood brain barrier.

"So what I believe is that we will find these leaks
occur in humans too. What we do not know is the extent of these leaks and
whether they have an effect on our health.

"Our bodies may be able to cope with it so there
will be no risks. But it could be found that, over time, the effects on
health could be much more significant."

Two years ago, a government inquiry into mobile phones
led by Sir William Stewart concluded there was no evidence of a risk to
health. But he advised that caution is taken over the use of mobiles by
children until more evidence on the impact on health is gathered.

Despite multi-million pound research across the world
since then, the effects of long-term use still remains unclear. But recently,
a handful of studies have begun to raise questions over safety. A survey
of 11,000 people in Sweden and Norway found that many suffer from headaches
and tiredness after using the gadgets.

Another study, by Swedish cancer specialist Lennart Hardell,
suggested that using the old analogue mobiles, popular in the early Nineties,
increased the risk of cancer.

His research is now at the centre of a lawsuit in the
US. Judges are deciding whether it provides enough proof of a link between
cancer and mobile phones for claimants to take manufacturers to court.

However, the growing body of research on mobiles and
health is leading some countries to consider action. China is debating
whether to force phone companies to reduce the levels of radiation. British
experts said last night there was no need for panic. They insisted that
more research was needed.